Basic Genetics and Heredity

Question 1

genetic material (DNA or RNA) packaged with proteins

Answer 1

chromosomes

Question 2

segment of DNA that contains info. to make one protein

Answer 2

gene

Question 3

different versions of a gene resulting in contrasting effect on a characteristic

eg: tallness or shortness

Answer 3

allele

Question 4

mendel’s principles of heredity

Answer 4

first hypothesis - second hypothesis (principle of dominance or recesiveness) - third hypothesis (law of segregation) - fourth hypothesis (law of independent assortment)

Question 5

inherited characteristics are controlled by factors that occur in pairs

Answer 5

first hypothesis

Question 6

one allele (dominant trait) in a pair may mask the other (recessive trait) and that dominant trait PREVENTS the recessive trait from having an effect

Answer 6

principle of dominance and recesiveness

Question 7

alleles for one gene segregate during gamete formation

during gamete formation, the alleles for each gene segregate from each other such that EACH GAMETE FORMED carries only ONE allele for EACH gene

Answer 7

law of segregation

Question 8

primarily because it has no fixed pattern

genes of different trait assort independent of each other during gamete formation

Answer 8

law of independent assortment

Question 9

alleles possessed by an indiv. for a particular gene

genetic make-up of gene shows the alleles present

Answer 9

genotype (TT - homozygous tall)

Question 10

observable characteristic of the indiv. with respect to that gene

external appearance dictated by genotype

Answer 10

phenotype (tall)

Question 11

individual with identical alleles for a gene

containing same types of alleles

also called PURE BREEDING

Answer 11

homozygous

Question 12

individual with 2 different alleles for a gene

Answer 12

heterogeneous

Question 13

used to determine the various combination of gene

determine genotype and phenotype of offspring in a parent test cross

Answer 13

punnett square method

Question 14

non-mendelian genetics

Answer 14

incomplete dominance - co-dominance - multiple alleles

Question 15

phenotype of the heterozygote is a 3rd trait that is DISTINCT and DIFFERENT from phenotypes of the homozygotes for the two alleles

eg: white and red rose = pink rose

Answer 15

incomplete dominance

Question 16

neither of the allele is masked, both is expressed in the organism

the phenotype of the heterozygote is a combination of the two phenotypes

cow with red hair and cow with white hair = offspring with bot red and white hair

Answer 16

co-dominance

Question 17

a gene still contains two alleles but there are more than two types of alleles with different degrees of dominance

eg: human blood

Answer 17

multiple alleles

Question 18

a single gene affects different phenotypes

eg: there is only one gene that determines pea flower color and pea seed color

Answer 18

pleiotropy

Question 19

a single phenotype is affected by two different genes

one gene depends on another gene for it to be expressed

eg: two genes need to have a dominant allele for a Labrador to have a yellow fur

Answer 19

epistasis

Question 20

a gene expression isnt limited to 2 diff. traits but instead several degrees of the trait

two or more genes contribute to the phenotype

eg: skin color isn’t just black or white, but different shades

Answer 20

polygenic inheritance

Question 21

genes that are found in the 23rd pair of chromosome/sex chromosome

Answer 21

sex-linked traits

Question 22

females have __ chromosome

Answer 22

XX

Question 23

males have __ chromosome

Answer 23

XY

Question 24

diseases that are what type of x-linked:

D-resistant rickets
oral-facial-digital syndrome I
fragile x syndrome

Answer 24

dominant x-linked

Question 25

diseases that are what type of x-linked:

red-green color blindness
hemophilia a and b
duchenne muscular dystrophy

Answer 25

recessive x-linked

Question 26

if a gene is passed in the Y chromosome, it will be passed only to ____

Answer 26

male offspring

Question 27

XY

Answer 27

healthy male

Question 28

XX

Answer 28

healthy female

Question 29

XᶜY

Answer 29

affected male

Question 30

XᶜYᶜ

Answer 30

affected female

Question 31

XᶜX

Answer 31

carrier female

Question 32

substances that can trigger immune response if foreign to the body

Answer 32

antigens

Question 33

how many antigens does blood type O have

Answer 33

none

Question 34

universal donor

Answer 34

blood type o